Antioxidant activities and bifidogenic properties of water-soluble crude polysaccharide preparations from flammulina velutipes and hypsizygus marmoreus mushrooms

Abstract

Antioxidant activities of water-soluble crude polysaccharides (WSCP) were determined using the DPPH radical-scavenging test and reducing-power assay. Bifidogenic properties of WSCP were evaluated by enumerating viable counts of Bifidobacterium longum CSCC 5089 in soymilk containing WSCP and monitoring a decrease in pH values during incubation. Results indicated that H. marmoreus WSCP had significantly (P<0.05) stronger antioxidant activities than those ofF. velutipes WSCP. Antioxidant activity of WSCP from H. marmoreus was 4.40 times stronger than those of F. velutipes WSCP with DPPH free radical-scavenging activity test, and 2.65 times stronger with the reducing-power assay. The viable counts of Bifidobacterium longum CSCC 5089 with powders of H. marmoreus and F. velutipes were significantly (P<0.05) higher than that of H. marmoreus and F. velutipes WSCP at 0, 12, 24, 3 6 and 48 b during fermentation. The viable counts of Bifidobacterium longum CSCC 5089 at 24 h with F. velutipes WSCP was 8.34 ± 0.06 log CFU/mL, which was not significantly (P>0.05) different than that of H. marmoreus WSCP (8.15 ± 0.08 log CFU/mL), while both results were significantly (P<0.05) higher than that of the control (7.36 ± 0.05 log CFU/mL). The pH values during incubation showed a pattern similar to that of the viable count of Bifidobacterium longum CSCC 5089. Our results showed that WSCP of H. marmoreus had significantly (P<0.05) higher DPPH radical scavenging activity and reducing power and both H. marmoreus and F. velutipes powders showed good bifidogenic effects on Bifidobacterium longum CSCC5089.